In the past, when the face was stimulated and monitored for facial expressions to indicate the depth of anesthesia, individual electrodes were often applied one at a time. The time required to apply individual electrodes was significant, especially when a full surgical operating crew was standing by or there were patients waiting for their turn in the surgery operating theater.
Additionally, when individual electrodes are used, there was the problem of multiple wires leading from the patient to any type of signal receiving device. It was, of course, important to keep track of which wire was connected to which electrode and where that electrode was placed on the face or other part of the patient's body. It was also important that the wires be hooked into the proper receptacle in any type of monitor. Again, valuable time was taken up in order to assure that the wires and electrodes had been properly placed on the patient and into the monitoring device.
In addition, as noted in the Background Of The Invention of the First Bennett Patent, there has been no expeditious method of monitoring the depth of unconsciousness of a patient under anesthesia. In this regard, anesthesia often seeks to provide a variety of results for the patient during surgery and invasive medical procedures. One such result is to provide oblivion through a state of unconsciousness. Another is to provide freedom from pain registration, conscious or unconscious. In seeking to achieve oblivion for the patient, however, the anesthesia can and often does paralyze muscle groups in varying degrees from partial paralysis to total paralysis.
In addition to the issues explained about the prior devices and methods explained in the First Bennett Patent, the surface electromyogram devices identified therein did not sense a sufficient number of facial muscle groups to procure sufficient response data. Similarly, they also have not provided a mechanism to readily assess the level of paralysis (neuro muscular blockade) of facial muscle groups brought about by anesthesia and to then quickly process this type of information in order to yield more accurate indicators of the depth of paralysis of the person, if any, and also of the depth of unconsciousness of a person in view of paralysis, if any.
As also shown in the prior art cited in the First Bennett Patent and in this specification, there are many electromyogram devices in the prior art for monitoring neuro muscular blockade during anesthesia ("NMBMs"). Another example of an NMBM is the Datex-Engstrom NeuroMuscular Transmission Module, M-NMT. This NMBM utilizes two stimulator electrodes secured to a patient's wrist, a return electrode secured to the patient's finger, and a sensor mounted on the patient's thumb to monitor the hypothenar muscle stimulated by the ulnar nerve. This NMBM is not designed for easily and reliably mounting on and sensing facial muscle groups and does not include any means of receiving output from the sensors, calculating and reporting consciousness indicators based on the output from the sensors, and also quickly and automatically processing neuro muscular blockade information to more accurately and automatically measure the depth of paralysis, if any, and the depth of consciousness of a person.
The following disclosures reflect the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant information available. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
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